Apparatus for separation of solid combustion residues from combustion gases



M. FREY April 30, 1935.

APPARATUS FOR SEPARATION OF SOLID COMBUSTION RESIDUES FROM COMBUSTIONGASES 5 Sheets-Sheet 1 Filed Dec. 24, 1930 flu wafer [Mantle/F s .14![only M. FREY A ril 30, 1935.

APPARATUS FOR SEPARATION OF SOLID COMBUSTION RESIDUES F ROM COMBUSTIONGASES Filed Dec. 24. 1930 S Sheets-Sheet 2 April 30, 1935. M. FREY1,999,589

APPARATUS FOR SEPARATION OF SOLID COMBUSTION RESIDUES FROM COMBUSTIONGASES Filed Dec 24, 1930 3 Sheets-Sheet 5 Mende/ W Patented 30, 1935PATENT OFFICE APPARATUS FOR SEPARATION OF SOLID COMBUSTION RESIDUES FROMCOMBUS- TION osses Mendel m Dordrecht, Netherlands Application December24, 1930, serial No. 504,544 In the Netherlands July 31, 19s.

2 Claim. (CL 183-22) This invention relates to apparatus for separatingthe solid particles from combustion gases.

Various types of apparatus for separating the solid particles fromcombustion gases are-known I and amongst these there exist centrifugalwashing devices. In this latter type of apparatus a spiral motion isimparted to the combustion gases so that the solid particles areseparated by being fiung outwardly onto the walls of the apparatus. i.At the same time, water is sprayed into the apparatus to assist theseparation of the particles and collect the same.

In some wet separators asheretofore constructed a very fine dispersionof the water was effected in order to obtain a good contact of the waterwith the fine dust particles. Thus fine nozzles were often employedwhich projected the water through the gases in the form of spray. Theuse of fine nozzles, however, has a threefold disadvantage, inasmuch as,firstly, due to the atomization of the water in the midst of the hotgases a considerable quantity of the water is uselessly evaporated,secondly, the nozzles are particularly susceptible to obstruction onaccount of their fineness, and thirdly a considerable quantity of thewashing water is carried away with the gas stream, the sheet iron partsof the flue being eventually damaged thereby.

Furthermore, in many of the known wet seption opposed to the flow of thecombustion gases for the purpose of more eihciently washing the same.Such a method, however, is unsuitable for use in cases where the gasesflow through the fiues at high speed since the spray tends to obstructtheir flow.

The object then of the present invention is to obviate the aforesaiddisadvantages and at the same time, to provide a'separator which is par?ticularly adapted for use in cases where the flow of the gases throughthe fiues is extremely rapid, the arrangement being such as to providethe minimum obstruction to the gases.

To this end, according to the invention, a spiral motion is imparted tothe gases and water is proiected from a point or points within a tubethrough which the said gases pass, to the walls of the said tube in theform of compact jets, substantially no atomization of the water takingplace until the same strikes the said walls, the water passing along thewalls in the form of a fine film and collecting the solid particlesfiung to th walls by centrifugal force.

In order to obtain the water film additional arators, the washing liquidis projected in a dimeconstruction, they requireonly a comparativelytrifling water consumption and besides the pressure loss caused by thisdevice is small, whilst the devices can be built-in in existinginstallations.

The spiral whirling motion of the fiue gases may be obtained by aspecial arrangement, for

instance by locating a spiral or helicoidal vane in the passage of thecombustion gases, whilst this motion can also be eflected by determiningthe form and the dimension with respect to the quantity of gas, fiowingthrough, in sucha way that the spiral motion results naturally andwithout other assistance. This motion can also be obtained with acylindrical flue passage by introducing the'gas in a tangentialdirection.

Also the mixing with water and the creation of the water film can beattained in diilerent manners.

In a suitable arrangement for carrying out the invention, the tube orflue in which the spiral motion takes place, is provided with a centraltube through which water under pressure is supplied. the said tube beingprovided with apertures or nozzles from which the water is ejected. Thesaid apertures or nozzles are sufliciently large to project the water incompact jets. In this way the water is partly divided into very finedrops as soon as it strikes against the wall and mixes with thecombustion gases, while a part immediately forms a water film flowingdown along thewall, in which water fllm the solid particles driven bycentrifugal force to the wall and the waterdrops are taken up anddrained off. Due to the relatively large size of the apertures ornozzles it is practically impossible for the same to become obstructed.4

The apparatus according to the invention can also serve for the removalof sulphur-dioxide by any chance present in the combustion gases. Inview of the permanent presence of sulphur in coal it is recommended tomanufacture the part of the channel and the device for supply of waterin question of acid resisting material.

Ash traps for application of the method according to the invention canbe of very simple construction, and they require only a comparativelytrifling water consumption. In addition, the pressure loss caused bythis device is small. whilst the devices can be built into existinginstallations.

In the accompanying drawings forming part hereof, several embodiments01' the invention are disclosed.

Figure 1 shows a diagrammatical view in section of a device according tothe invention;

Figure 2 is a detail partly in section;

Figure 3 is the detail 01' Figure 2 in cross section;

Figure 4 is a device according to the invention applied to a flue,whilst Figures 5, 6 and 7 disclose how a device according to theinvention is built into a flue 01' a boiler;

Figures 8, 9 and 10 ultimately represent in two vertical sectionsrespectively and in a plan view an embodiment of a device which isconstructed with elements assembledtogether by means of bolts.

The apparatus according to Figure 1 consists of a vertical tube I whichis connected with the flue by means of a bend 2. The cross section ofthe tube I is preferably not larger than that of the flue. In the tube Iis disposed a water supply pipe 3 having a closed end through whichwater can be supplied under pressure and which is provided. withapertures as is shown in the Figures 2 and 3, from which at the placesA, B and C water may be ejected with violence to the wall oi the tube I.Further a helicoidal vane l is placed in the tube I. The tube Iterminates just above the bottom of a closed receptacle 5 which isprovided with an outlet 6. The combustion gases which pass through thebend 2 into the vertical tube I are mixed with the water that is'atomized against the wall or tube I, so that the solid particles aremade heavier. Then the gases are brought in a spiral motion by means ofthe helicoidal vane 4, so that they will cover a longer path through thetube I and the heavier particles will be flung to the wall owing to thecentrifugal force. Along this wall a water film is formed by the waterin which the particles are taken up and by which they are drained offdownwardly. The combustion gases are discharged from the receptaclethrough the outlet Ii whilst the water and the solid combustion residuesaccumulate in the lower part of the vessel and are drained ofl throughan outlet pipe I and an open drain box 8. Sludge tends to accumulate onthe bottom of receptacle 5land may clog the opening of outlet pipe I. Bymeans of a pipe 9 terminating near the inlet of pipe I, water may beejected from pipe 9 so as to keep the opening of the pipe 'I clear andfree, and thus prevents obstruction oi! the latter.

It should be remarked here that in connection with the examples ofFigures 1 and 3 that the water film results from the injected water fromthe tube 3, but that with these and other installations the water filmcan also be obtained by a separate supply of water.

In Figure 4 an embodiment is shown, in which a device according toFigure 1 is disposed in connection with the flue I5 of a boiler leadingto the stack. In the flue I5 a damper (valve) I6 or movable partition isplaced. In front of the damper It the flue is connected to the bend 2 ofthe device by means of a tube I1, whilethe outlet Ii 01 the deviceinterconnects with the flue at a place behind the damper.

With the boiler installation shown in Figures 5, 6 and 7 a similardevice is employed to that shown in Figure l. The device which isentirely built-in in the flue of the boiler consists of four.

tubes I, each with a water supply pipe In the device according toFigures 1, 4, 5 or 8 the position of the helicoidal vane and the watersupply pipe may be reversed (interchanged).

In the example according to Figures 8, 9 and 10 the tubes I are mountedon a frame I8 consisting of three separate inter-communicatingcompartments, the member I8 is provided with an outlet I! for thecombustion gases and 0! connections 20 for the discharge of the wateriniected into the device and containing the combustion residue.

The elements of which the-device consists are provided on the connectingplace with flanges 2| which serve for connecting the separate elementsto a fixed unit, for instance by means of thread bolts.

This embodiment makes it possible to keep in stock the elements requiredfor the assembly of the device according to the invention in order todeliver them when required. In this way the capacity of the device canbe fitted to the boiler installation, for which it is intended. It forinstance, the passage of one of the tubes I is calculated for thedischarge of the combustion gases of a boiler installation with a firingcapacity of one ton fuel per hour, one single section of the frame I8being sufilcient for said capacity.

Such a single section is shown in Figure 9 which.

is a vertical section on the line IX-IX of Figure 8.

It required in this case one oi the tubes I can be employed for thesupply of the combustion gases from the fireplace and the other tube Ias discharge for the gases, cleansed of the solid par-.

ticles.

Devices of large capacity are composed according to the invention of twoor more sections of the frame I8, with the corresponding tubes Iassembled to one single unit.

I claim:-

1. Apparatus for separating the solid particles from combustion gasescontaining them, including in combination, a receptacle having a channeltherethrough of which at least a portion of its length is subdividedinto a plurality of parallel channels disposed in substantially uprightposition, means for imparting a whirling motion to the gases in each 01said parallel channels in order to project the solid particles of thegases centrifugally against the walls thereof while said gases passdownward through the channels, said means comprising a stationaryhelicoidal vane disposed in each of said parallel channels and havingthe axis thereof corresponding with the axis of the respective channelin which it is located, and a water supply tube disposed directly abovethe helicoidal vane' in each of said parallel channels radiallyprojecting a plurality of continuous, solid and merged Jets of water inthe form of a radially divergent and continuous water curtain directlyagainst the interior wall in each' or said parallel channels above thehelicoidal vane therein and thereby simultaneously producing acontinuous and unbroken sheet or veil of water trickling down upon saidinterior wall in each oi! said channels and a zone of rebounding waterspray adjacent the sheet or veil of water on said interior wall thereinin order to entrain the solid particles or the gases in the watertrickling down on said interior wall, the helicoidal vane in each or theparallel channels making contact with the gases solely below the waterJets in substantially washed and cleaned condition of said gases.

2. Apparatus for separating the solid particles .i'rom combustion gasescontaining them, including in combination, a receptacle havlns a channeltherethroug'n of which at least a portion of its length is substantiallyupria'ht in position, means for imparting a whirlingmotion to the gasesin the upright portion of the channel in order to project the solidparticles oi the gasescentrifugallyagainstthewallsoisaidchannelwhilesaid gases pass downward through the channel, said means comprising astationary helicoldal vane in said channel whose axis corresponds withtheaxisotsaiduprishtportionoithechannel. andawatermppytubedisposeddirectiyabove said helicoidal vane within said channelradially projecting a plurality of continuous, solidandmcrsedictsodwaterintheiormoiradlallydb.

vex-gent and continuous-curtain directly against the interior wall ofsaid upright channel portion above said helicoidal vane and therebysimultaneously producing a continuous and unbroken sheet or veil ofwater trickling downward upon said interior wall and a zone ofrebounding water spray adjacent the sheet or veil of water on the wallinordertoentrain the solidparticleaoithegases in the watertrickling'down upon said wall, the helicoidal vane making contact withthe gases solely below said water jets in substantially washed andcleaned condition of said gases.

